Recent advances in cellular immunology and immunogenetics have provided, within the murine system, the technology necessary to critically investigate the multiple mechanisms which comprise "tumor immunology." It is the intent of this research proposal to use these recent advances to investigate the cellular and genetic requirements which are necessary for T-killer (Tk) and T-suppressor (Ts) cell generation with specificity for either the common or the unique tumor associated antigens. These will involve an analysis of the phenotypic properties (Lyt, Ia, Thy-1) of both the accessary macrophage and the lymphocyte subpopulations as well as their temporal sequence of involvement within the anti-tumor response. We also propose to establish, using f1-hybrids and appropriate MHC congenic strains, whether the ability to mount effective Tk and Ts cell responses is under Ir gene control. The ultimate goal of these studies will be to develop the necessary expertise so that host-tumor interactions can be investigated as an integrated system. This will be accomplished by providing experimental verification of the relationships which exist between effector and regulating mechanisms, their cellular as well as their genetic constraints, within a well-characterized murine model system.